CA2473276C - Method for inspecting a titanium-based component - Google Patents
Method for inspecting a titanium-based component Download PDFInfo
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- CA2473276C CA2473276C CA2473276A CA2473276A CA2473276C CA 2473276 C CA2473276 C CA 2473276C CA 2473276 A CA2473276 A CA 2473276A CA 2473276 A CA2473276 A CA 2473276A CA 2473276 C CA2473276 C CA 2473276C
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F1/00—Etching metallic material by chemical means
- C23F1/10—Etching compositions
- C23F1/14—Aqueous compositions
- C23F1/16—Acidic compositions
- C23F1/20—Acidic compositions for etching aluminium or alloys thereof
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/8803—Visual inspection
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/20—Metals
- G01N33/208—Coatings, e.g. platings
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2260/00—Function
- F05B2260/80—Diagnostics
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
- F05C2201/00—Metals
- F05C2201/02—Light metals
- F05C2201/021—Aluminium
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
- F05C2201/00—Metals
- F05C2201/04—Heavy metals
- F05C2201/0403—Refractory metals, e.g. V, W
- F05C2201/0412—Titanium
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/91—Investigating the presence of flaws or contamination using penetration of dyes, e.g. fluorescent ink
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- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Pathology (AREA)
- Physics & Mathematics (AREA)
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- General Physics & Mathematics (AREA)
- General Health & Medical Sciences (AREA)
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- Analytical Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Medicinal Chemistry (AREA)
- Food Science & Technology (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Metallurgy (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Investigating And Analyzing Materials By Characteristic Methods (AREA)
- ing And Chemical Polishing (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
- Sampling And Sample Adjustment (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
A process for detecting an aluminum-based material deposited onto a titanium- based gas turbine engine component during engine operation is disclosed. The process comprises immersing at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component. The acid solution comprises sodium fluoride, sulphuric acid and water. The etched component may then be removed from the solution and visually inspected for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
Description
METHOD FOR INSPECTIhTG A TITANIUM-BASED COMPONENT
FIELD OF THE INVENTION
The present invention generally relates to methods for inspecting titanium-based components, such as the components of a gas turbine engine, after engine operation.
More particularly, this invention relates to an inspection method for detecting the presence of aluminum-based material deposited on titanium-based gas turbine engine components.
BACKGROUND OF THE INVENTION
Titanium-based materials are useful because of their relatively low weight and high strength over a wide range of operating temperatures. Titanium or titanium alloys often are the material of choice for high performance gas turbine engine components, such as the fan rotor, fan blades, compressor disk and compressor blades. A
wide range of titanium alloys are available, each of which confer a particular combination of characteristics to the component. For example, some gas turbine compressor blades are made of the commercially available Ti-6A1-4V alloy.
The efficiency of gas turbine engines is dependent, in part, on the ability of the above titanium-based and other engine components to combine air and products of combustion, to intended pathways. Leakage from such design flowpaths can reduce engine performance and efficiency and thus gas turbine engine designers have developed a variety of sealing arrangements, such as abradable seals, to work in conjunction with other components to reduce or control leakage. For example, abradable seals are used on the shrouds of compressors to insure efficient operation of the engine by minimizing gas leakage in the compressor and turbine sections.
Although the engine is typically designed and manufactured to precise dimensional tolerances, centrifugal and themnal expansion of the rotating and stationary members makes it difficult to achieve zero clearances. Thu:m, abradable seals often are employed on surfaces of the stationary member allo~~ing penetration of rotating blades into the seal.
Some modern gas turbine engines employ titanium alloy rotor blades and an AISi coated seal. During operation., the titanium alloy blades may contact and rub into casings or adjacent hardware coated with AISi. The condition of the blade after operation can vary depending on the severity of the rub. Severe rubs may result in over heating of the blade tip with a range of conditions. varying from an associated color tint on the tip, transformation of the blade tip microstructure to deformation of the blade tip. However, there are no visual indications for blades that experienced mild contact into the AISi coating resulting in the deposit of aluminum on the blade.
Such deposit onto the blades is aerodynamically undesirable and may result in decreased engine performance and efficiency. Thus, if a blade rub is suspected, all of the blades are removed from the engine and replaced.
Accordingly, there exists a need for a nondestructive inspection technique that identifies the presence of aluminurr~-based material deposited on titanium-based components during engine operation. The present invention satisfies this need.
BRIEF DESCRIPTION OF T HE TI~VENTION
In one embodiment of the invention, a process for detecting an aluminum-based material deposited onto a tit4:nium-based gas turbine engine component during engine operation is disclosed. The process comprises immer;>ing at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component, wherein the acid solution. comprises sodium fluoride, sulphuric acid and water. The process further ccmprises removing the etched component from the solution and visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
In another embodiment of the invention, a process for detecting an aluminum-based material deposited onto a titanium-based gas turbine en;~ine component during engine operation, comprises immersing, for between about 45 seconds and about 3 minutes, at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component. The acid solution comprises, per liter: i) about 15 g/liter of sodium fluoride; ii) about 75 g/liter of sulphuric acid having a density of about 1.84; and iii) balance water. The process further comprises removing the etched component from the solution; washing the etched component in water, followed by drying; and visually inspecting the etched component under magnified conditions for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based materia:L
In accordance with a further embodiment, a process for detecting an aluminum-based material deposited onto a titanium-based gas turbine engine component during engine operation comprises swab etching at Ieast a portion of the titanium-based component, which has been subjected to engine operation, with an acid solution to form an etched component, the acid solution comprising i) sodium fluoride, ii) sulphuric acid and iii) water. The process further comprises visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
In accordance with further e~ribodiments of vhe invention, calcium fluoride, potassium fluoride or hydrofluoric acid may be substituted for the sodium fluoride constituent.
ERIEF DESCRIPTION OF TI-iE DR.AWIN(JS
Figure 1 shows, at about ~x magnification, the condition of a blade that has experienced tip rub with an AISi coating during engine operation.
Figure 2 shows, at about Sx magnification, the condition of another blade that has experienced tip rub with an .~llSi coating during engine operation.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is usefixl in the inspection of titanium-based gas turbine engine components subjected to engine operation. As used herein, the term "titanium-based"
FIELD OF THE INVENTION
The present invention generally relates to methods for inspecting titanium-based components, such as the components of a gas turbine engine, after engine operation.
More particularly, this invention relates to an inspection method for detecting the presence of aluminum-based material deposited on titanium-based gas turbine engine components.
BACKGROUND OF THE INVENTION
Titanium-based materials are useful because of their relatively low weight and high strength over a wide range of operating temperatures. Titanium or titanium alloys often are the material of choice for high performance gas turbine engine components, such as the fan rotor, fan blades, compressor disk and compressor blades. A
wide range of titanium alloys are available, each of which confer a particular combination of characteristics to the component. For example, some gas turbine compressor blades are made of the commercially available Ti-6A1-4V alloy.
The efficiency of gas turbine engines is dependent, in part, on the ability of the above titanium-based and other engine components to combine air and products of combustion, to intended pathways. Leakage from such design flowpaths can reduce engine performance and efficiency and thus gas turbine engine designers have developed a variety of sealing arrangements, such as abradable seals, to work in conjunction with other components to reduce or control leakage. For example, abradable seals are used on the shrouds of compressors to insure efficient operation of the engine by minimizing gas leakage in the compressor and turbine sections.
Although the engine is typically designed and manufactured to precise dimensional tolerances, centrifugal and themnal expansion of the rotating and stationary members makes it difficult to achieve zero clearances. Thu:m, abradable seals often are employed on surfaces of the stationary member allo~~ing penetration of rotating blades into the seal.
Some modern gas turbine engines employ titanium alloy rotor blades and an AISi coated seal. During operation., the titanium alloy blades may contact and rub into casings or adjacent hardware coated with AISi. The condition of the blade after operation can vary depending on the severity of the rub. Severe rubs may result in over heating of the blade tip with a range of conditions. varying from an associated color tint on the tip, transformation of the blade tip microstructure to deformation of the blade tip. However, there are no visual indications for blades that experienced mild contact into the AISi coating resulting in the deposit of aluminum on the blade.
Such deposit onto the blades is aerodynamically undesirable and may result in decreased engine performance and efficiency. Thus, if a blade rub is suspected, all of the blades are removed from the engine and replaced.
Accordingly, there exists a need for a nondestructive inspection technique that identifies the presence of aluminurr~-based material deposited on titanium-based components during engine operation. The present invention satisfies this need.
BRIEF DESCRIPTION OF T HE TI~VENTION
In one embodiment of the invention, a process for detecting an aluminum-based material deposited onto a tit4:nium-based gas turbine engine component during engine operation is disclosed. The process comprises immer;>ing at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component, wherein the acid solution. comprises sodium fluoride, sulphuric acid and water. The process further ccmprises removing the etched component from the solution and visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
In another embodiment of the invention, a process for detecting an aluminum-based material deposited onto a titanium-based gas turbine en;~ine component during engine operation, comprises immersing, for between about 45 seconds and about 3 minutes, at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component. The acid solution comprises, per liter: i) about 15 g/liter of sodium fluoride; ii) about 75 g/liter of sulphuric acid having a density of about 1.84; and iii) balance water. The process further comprises removing the etched component from the solution; washing the etched component in water, followed by drying; and visually inspecting the etched component under magnified conditions for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based materia:L
In accordance with a further embodiment, a process for detecting an aluminum-based material deposited onto a titanium-based gas turbine engine component during engine operation comprises swab etching at Ieast a portion of the titanium-based component, which has been subjected to engine operation, with an acid solution to form an etched component, the acid solution comprising i) sodium fluoride, ii) sulphuric acid and iii) water. The process further comprises visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
In accordance with further e~ribodiments of vhe invention, calcium fluoride, potassium fluoride or hydrofluoric acid may be substituted for the sodium fluoride constituent.
ERIEF DESCRIPTION OF TI-iE DR.AWIN(JS
Figure 1 shows, at about ~x magnification, the condition of a blade that has experienced tip rub with an AISi coating during engine operation.
Figure 2 shows, at about Sx magnification, the condition of another blade that has experienced tip rub with an .~llSi coating during engine operation.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is usefixl in the inspection of titanium-based gas turbine engine components subjected to engine operation. As used herein, the term "titanium-based"
includes titanium alloys, as well as substantially pure titanium. The following description is provided with reference to gas turbine engine components, particularly blades, but it will be understood that the present invention also is applicable to any titanium-based substrate whiclvi may have contacted an aluminum-based material. As also used herein, the term "aluminum-based" includes substantially pure aluminum, as well as aluminum in combination with other substances.
In accordance with one embodLiment of the present invention, a titanium-based blade, which has been subjected to engine service, is inspected to determine if an aluminum-based material has been deposited onto the component. Such aluminum deposit may occur as a result of the blade tip contacting an aluminium-based coating, such as an AlSi coating, of an abradable seal during a rvb. An alurr~inum deposit also may result from contact with aluminum-based hardware, such as a ;>hroud.
The blade may be removed fre~m the engine for inspection and rinsed with water prior to inspection. According to ores aspect of the invention, at least a portion of the blade requiring inspection, such as the blade tip, is immersed in an acid solution.
Alternatively, an entire component may be immersed, if desired.
The acid solution may comprise sodium fluoride, sulphuric acid and water. In one embodiment, the solution comprises, per liter, ab~ut 5 t:o about 50 g sodium fluoride, about 50 to about 100 g sulphuric acid, balance water. 'I he duration of the immersion time is dependent upon the ceencentration of the soluti~~n. For example, with respect to the above, at least a, portion of the blade may be immersed in the solution for between about 1 and about 5 minutes (for about 5 g sodium fluoride) and about seconds to about 1 minute (for about 50 g sodium fluoride). :Preferably, the solution comprises, per liter, about 1 S g sodium fluoride, about. 75 g sulphuric acid having a density of about 1.84, balance water, and the eomponer~t is immersed in the solution for between about 45 seconds and about 3 minutes. Al l subranges therebetween also are included in the present invention.
Alternatively, potassium fluoride, calcium fluoride or hydrofluoric acid may be substituted for the sodium fluoride constituent, in the amounts described above for the sodium fluoride. I3owever, longer immersion times, such as about 4x or greater than the above described times, may be required if potassium fluoride or calcium fluoride is employed. If hydrofluoric acid is substituted for the. sodium fluoride constituent, shorter immersion times, such as about 1/2x or less than the above described immersion times for sodium fluoride may be employed. I~owever, use of hydrofluoric acid may have secondary effects on the exposed component.
The acid solution composition is particularly effeci:ive at normal temperatures between about 15°C and about: 25'C. The solution also may be agitated prior to and during immersion. If desired., the solution may be recharged or replenished during use by adding further suitable amounts of the solution constituents, particularly sodium fluoride, to maintain desired etching duration times.
After immersion, the blade may be removed from the solution, washed with water and air dried. The blade then may be visually inspected for the appearance of dark areas, which indicate rubbed surfaces or surfaces of the blades exposed to an aluminum-based material, such as AISi coating. These dark areas are in contrast to the areas of lighter appearance on the blade, which indicate non-rubbed areas or areas of the blade that have not contacted the aluminum-based material. 'Che dark areas of contact may appear as black lines on the blades. Visual inspection at a magnification of about 4x to about 25x, preferably about lOx, is particularly usefa~l for inspection.
Referring to FICrS. 1 and 2, shown are tips of two titanium alloy blades which have contacted an AISi seal coating during engine operation. Upon application of the preferred process of the present invention, a black line (indicated by arrows on FIGS. 1 and 2 at about Sx magnification) was visible on each blade. Advantageously, if such a contrasting dark area is not shown on the blade, the blade may be returned to operation and not unnecessarily scrapped.
Alternatively, it may not be necessary to remove the blade from the engine prior to application of solution. For example, a "swab etch" method may be employed by repeatedly applying the afore-described solution onto th.e blade with a saturated cloth, cotton wool material or other suitable applicator so that the blade may be exposed to 12687'7 the solution for a suitable time, such as the duration comparable to that of the immersion method. The blade then may be washed with water, which can be applied with the use of any suitable applicator such as a cloth or spray device, and dried.
An advantage of the present invention is providing a nondestructive inspection technique that comprises minimal steps and is cost effective to implement. The inspection may be set up easily and inexpensively, without the need for special, complicated equipment. moreover, operators also may be readily trained in the inspection process.
Another advantage of the present invention is that the process removes less than 0.0001 inches (2.564 pm) from the surface of the component. 'Thus, the components will meet dimensional requirements after inspection and. non-rubbed components may be readily returned to service.
A further advantage of the present invention is that it employs an uncomplicated etch immersion or swab etch technique, which may readily and quickly reveal component rub or exposure to an aluminum-based material without the requirement of further processing of the part for inspection.
While various embodiments are described herein, it will be appreciated from the specification that various combinations of elements, 'variations or improvements therein may be made by those skilled in the art, anal are within the scope of the invention.
In accordance with one embodLiment of the present invention, a titanium-based blade, which has been subjected to engine service, is inspected to determine if an aluminum-based material has been deposited onto the component. Such aluminum deposit may occur as a result of the blade tip contacting an aluminium-based coating, such as an AlSi coating, of an abradable seal during a rvb. An alurr~inum deposit also may result from contact with aluminum-based hardware, such as a ;>hroud.
The blade may be removed fre~m the engine for inspection and rinsed with water prior to inspection. According to ores aspect of the invention, at least a portion of the blade requiring inspection, such as the blade tip, is immersed in an acid solution.
Alternatively, an entire component may be immersed, if desired.
The acid solution may comprise sodium fluoride, sulphuric acid and water. In one embodiment, the solution comprises, per liter, ab~ut 5 t:o about 50 g sodium fluoride, about 50 to about 100 g sulphuric acid, balance water. 'I he duration of the immersion time is dependent upon the ceencentration of the soluti~~n. For example, with respect to the above, at least a, portion of the blade may be immersed in the solution for between about 1 and about 5 minutes (for about 5 g sodium fluoride) and about seconds to about 1 minute (for about 50 g sodium fluoride). :Preferably, the solution comprises, per liter, about 1 S g sodium fluoride, about. 75 g sulphuric acid having a density of about 1.84, balance water, and the eomponer~t is immersed in the solution for between about 45 seconds and about 3 minutes. Al l subranges therebetween also are included in the present invention.
Alternatively, potassium fluoride, calcium fluoride or hydrofluoric acid may be substituted for the sodium fluoride constituent, in the amounts described above for the sodium fluoride. I3owever, longer immersion times, such as about 4x or greater than the above described times, may be required if potassium fluoride or calcium fluoride is employed. If hydrofluoric acid is substituted for the. sodium fluoride constituent, shorter immersion times, such as about 1/2x or less than the above described immersion times for sodium fluoride may be employed. I~owever, use of hydrofluoric acid may have secondary effects on the exposed component.
The acid solution composition is particularly effeci:ive at normal temperatures between about 15°C and about: 25'C. The solution also may be agitated prior to and during immersion. If desired., the solution may be recharged or replenished during use by adding further suitable amounts of the solution constituents, particularly sodium fluoride, to maintain desired etching duration times.
After immersion, the blade may be removed from the solution, washed with water and air dried. The blade then may be visually inspected for the appearance of dark areas, which indicate rubbed surfaces or surfaces of the blades exposed to an aluminum-based material, such as AISi coating. These dark areas are in contrast to the areas of lighter appearance on the blade, which indicate non-rubbed areas or areas of the blade that have not contacted the aluminum-based material. 'Che dark areas of contact may appear as black lines on the blades. Visual inspection at a magnification of about 4x to about 25x, preferably about lOx, is particularly usefa~l for inspection.
Referring to FICrS. 1 and 2, shown are tips of two titanium alloy blades which have contacted an AISi seal coating during engine operation. Upon application of the preferred process of the present invention, a black line (indicated by arrows on FIGS. 1 and 2 at about Sx magnification) was visible on each blade. Advantageously, if such a contrasting dark area is not shown on the blade, the blade may be returned to operation and not unnecessarily scrapped.
Alternatively, it may not be necessary to remove the blade from the engine prior to application of solution. For example, a "swab etch" method may be employed by repeatedly applying the afore-described solution onto th.e blade with a saturated cloth, cotton wool material or other suitable applicator so that the blade may be exposed to 12687'7 the solution for a suitable time, such as the duration comparable to that of the immersion method. The blade then may be washed with water, which can be applied with the use of any suitable applicator such as a cloth or spray device, and dried.
An advantage of the present invention is providing a nondestructive inspection technique that comprises minimal steps and is cost effective to implement. The inspection may be set up easily and inexpensively, without the need for special, complicated equipment. moreover, operators also may be readily trained in the inspection process.
Another advantage of the present invention is that the process removes less than 0.0001 inches (2.564 pm) from the surface of the component. 'Thus, the components will meet dimensional requirements after inspection and. non-rubbed components may be readily returned to service.
A further advantage of the present invention is that it employs an uncomplicated etch immersion or swab etch technique, which may readily and quickly reveal component rub or exposure to an aluminum-based material without the requirement of further processing of the part for inspection.
While various embodiments are described herein, it will be appreciated from the specification that various combinations of elements, 'variations or improvements therein may be made by those skilled in the art, anal are within the scope of the invention.
Claims (26)
1. A process for detecting an aluminum-based material deposited onto a titanium-based gas turbine engine component during engine operation when there is not a visual indication of at least a portion of the aluminum-based material on the component, consisting of the sequential steps of.
immersing at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component, the acid solution comprising sodium fluoride, sulphuric acid and water;
removing the etched component from the solution; and visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
immersing at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component, the acid solution comprising sodium fluoride, sulphuric acid and water;
removing the etched component from the solution; and visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
2. The process of claim 1, wherein the titanium-based component is a titanium alloy blade.
3. The process of claim 1, wherein the acid solution comprises, per liter i) 15 g/liter of sodium fluoride; ii) 75 g/liter of sulphuric acid having a density of about 1.84; and iii) balance water, and at least a portion of the component is immersed in the acid solution for between 45 seconds and 3 minutes.
4. The process of claim 2, wherein only a blade tip is immersed in the solution.
5. The process of claim 1, wherein the entire component is immersed in the solution.
6. The process of claim 1, wherein the etched component is visually inspected at a magnification of 4x to 25x.
7. The process of claim 6, wherein the etched component is visually inspected at a magnification of 10x.
8. The process of claim 1, wherein the acid solution comprises, per liter i) 5 to 50 g/liter of sodium fluoride; ii) 50 to 100 g/liter of sulphuric acid having a density of about 1.84; and iii) balance water.
9. The process of claim 8, wherein the at least a portion of the component is immersed in the solution from between 1 minute and 5 minutes.
10. The process of claim 8, wherein the at least a portion of the component is immersed in the solution between 25 seconds and 1 minute.
11. The process of claim 1, wherein the aluminum-based material is AlSi.
12. A process for detecting an aluminum-based material deposited onto a titanium-based gas turbine engine component during engine operation when there is not a visual indication of at least a portion of the aluminum-based material on the component, consisting of the sequential steps of:
immersing, for between 45 seconds and 3 minutes, at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component, the acid solution comprising, per liter:
i) 15 g/liter of sodium fluoride;
ii) 75 g/liter of sulphuric acid having a density of 1.84; and iii) balance water;
removing the etched component from the solution;
washing the etched component in water, followed by drying; and visually inspecting the etched component under magnified conditions for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
immersing, for between 45 seconds and 3 minutes, at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component, the acid solution comprising, per liter:
i) 15 g/liter of sodium fluoride;
ii) 75 g/liter of sulphuric acid having a density of 1.84; and iii) balance water;
removing the etched component from the solution;
washing the etched component in water, followed by drying; and visually inspecting the etched component under magnified conditions for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
13. The process of claim 12, wherein the titanium-based component is a titanium alloy blade.
14. The process of claim 13, wherein only a blade tip is immersed in the solution.
15. The process of claim 12, wherein the entire component is immersed in the solution.
16. The process of claim 12, wherein the etched component is visually inspected at a magnification of 4x to 25x.
17. The process of claim 16, wherein the etched component is visually inspected at a magnification of 10x.
18. The process of claim 12, wherein the aluminum-based material is AlSi.
19. A process for detecting an aluminum-based material deposited onto a titanium-based gas turbine engine component during engine operation when there is not a visual indication of at least a portion of the aluminum-based material on the component, consisting of the sequential steps of:
swab etching at least a portion of the titanium-based component, which has been subjected to engine operation, with an acid solution to form an etched component, the acid solution comprising sodium fluoride, sulphuric acid and water;
and visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
swab etching at least a portion of the titanium-based component, which has been subjected to engine operation, with an acid solution to form an etched component, the acid solution comprising sodium fluoride, sulphuric acid and water;
and visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
20. The process of claim 19, wherein the swab etching step comprises saturating an applicator with the acid solution and repeatedly applying the acid solution to at least a portion of the titanium-based component.
21. The process of claim 20, wherein the applicator is selected from the group consisting of a cloth, a cotton wool material and spray device.
22. A process for detecting an aluminum-based material deposited onto a titanium-based gas turbine engine component during engine operation when there is not a visual indication of at least a portion of the aluminum-based material on the component, consisting of the sequential steps of:
immersing at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component, the acid solution comprising i) one of calcium fluoride, potassium fluoride and hydrofluoric acid, ii) sulphuric acid and iii) water; removing the etched component from the solution; and visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
immersing at least a portion of the titanium-based component, which has been subjected to engine operation, into an acid solution to form an etched component, the acid solution comprising i) one of calcium fluoride, potassium fluoride and hydrofluoric acid, ii) sulphuric acid and iii) water; removing the etched component from the solution; and visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
23. A process for detecting an aluminum-based material deposited onto a titanium-based gas turbine engine component during engine operation when there is not a visual indication of at least a portion of the aluminum-based material on the component, consisting of the sequential steps of:
swab etching at least a portion of the titanium-based component, which has been subjected to engine operation, with an acid solution to form an etched component, the acid solution comprising i) one of calcium fluoride, potassium fluoride and hydrofluoric acid, ii) sulphuric acid and iii) water; and visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
swab etching at least a portion of the titanium-based component, which has been subjected to engine operation, with an acid solution to form an etched component, the acid solution comprising i) one of calcium fluoride, potassium fluoride and hydrofluoric acid, ii) sulphuric acid and iii) water; and visually inspecting the etched component for dark areas in contrast to light areas, the dark areas indicating deposited aluminum-based material.
24. The process of claim 1, wherein the component is rinsed with water after removing the component from the solution and prior to visually inspecting the etched component.
25. The process of claim 22, wherein the solution comprises i) one of calcium fluoride and potassium fluoride ii) sulphuric acid and iii) water.
26. The process of claim 23, wherein the solution comprises i) one of calcium fluoride and potassium fluoride ii) sulphuric acid and iii) water.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US10/622,304 | 2003-07-17 | ||
| US10/622,304 US7097783B2 (en) | 2003-07-17 | 2003-07-17 | Method for inspecting a titanium-based component |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2473276A1 CA2473276A1 (en) | 2005-01-17 |
| CA2473276C true CA2473276C (en) | 2011-08-23 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2473276A Expired - Fee Related CA2473276C (en) | 2003-07-17 | 2004-07-08 | Method for inspecting a titanium-based component |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US7097783B2 (en) |
| EP (1) | EP1498731B1 (en) |
| JP (1) | JP4651983B2 (en) |
| BR (1) | BRPI0402741B1 (en) |
| CA (1) | CA2473276C (en) |
| SG (1) | SG108981A1 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7374404B2 (en) * | 2005-09-22 | 2008-05-20 | General Electric Company | Methods and apparatus for gas turbine engines |
| FR2961598B1 (en) * | 2010-06-21 | 2012-07-27 | Snecma | PROCESS FOR CHECKING A TITANIUM OR TITANIUM ALLOY FOR THE DETECTION OF MACHINING DEFECTS |
| US9804058B2 (en) | 2014-02-27 | 2017-10-31 | Pratt & Whitney Canada Corp. | Method of facilitating visual detection of a crack in a component of a gas turbine engine |
| DE102018201668B4 (en) * | 2018-02-05 | 2023-10-12 | MTU Aero Engines AG | Method for the non-destructive testing of workpiece surfaces |
| FR3087794B1 (en) * | 2018-10-26 | 2020-10-30 | Safran Aircraft Engines | CHEMICAL MATIFICATION PROCESS |
| CN113583679B (en) * | 2021-07-27 | 2022-10-28 | 光华科学技术研究院(广东)有限公司 | Ferrite surface roughening liquid and application thereof in ferrite surface roughening treatment and metallization treatment |
Family Cites Families (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2827402A (en) * | 1955-10-24 | 1958-03-18 | Gen Electric | Method of pickling titanium and titanium alloys |
| GB1344711A (en) * | 1971-06-17 | 1974-01-23 | Rolls Royce | Method of etching a titanium or titanium alloy part |
| US4063644A (en) | 1973-07-13 | 1977-12-20 | Grumman Aerospace Corporation | Process for nondestructive inspection |
| US4318792A (en) | 1980-07-07 | 1982-03-09 | Trw Inc. | Process for depositing forging lubricant on titanium workpiece |
| US4874434A (en) * | 1988-05-16 | 1989-10-17 | Kerr-Mcgee Chemical Corporation | Method of treating a titanium structure |
| US5484665A (en) | 1991-04-15 | 1996-01-16 | General Electric Company | Rotary seal member and method for making |
| FR2677670B1 (en) * | 1991-06-12 | 1993-09-10 | Snecma | ACID ATTACK BATH OF TITANIUM ALLOYS BEFORE MACROGRAPHIC ANODIC OXIDATION. |
| FR2677669B1 (en) | 1991-06-12 | 1993-09-10 | Snecma | REVELATION BATH AFTER PHOSPHORIC ANODIZATION ON TITANIUM ALLOY. |
| JPH06128759A (en) * | 1992-10-13 | 1994-05-10 | Nippon Steel Corp | Corrosive liquid revealing metallic structure of aluminum alloy and revealing method |
| US5705082A (en) * | 1995-01-26 | 1998-01-06 | Chromalloy Gas Turbine Corporation | Roughening of metal surfaces |
| US5976695A (en) | 1996-10-02 | 1999-11-02 | Westaim Technologies, Inc. | Thermally sprayable powder materials having an alloyed metal phase and a solid lubricant ceramic phase and abradable seal assemblies manufactured therefrom |
| US5853561A (en) | 1997-06-23 | 1998-12-29 | The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration | Method for surface texturing titanium products |
| JP2000002670A (en) * | 1998-06-12 | 2000-01-07 | Ishikawajima Harima Heavy Ind Co Ltd | Etching inspection method for titanium alloy product and test piece for etching inspection |
| US6401537B1 (en) | 1999-07-02 | 2002-06-11 | General Electric Company | Titanium-based alloys having improved inspection characteristics for ultrasonic examination, and related processes |
| US6899339B2 (en) * | 2001-08-30 | 2005-05-31 | United Technologies Corporation | Abradable seal having improved durability |
-
2003
- 2003-07-17 US US10/622,304 patent/US7097783B2/en not_active Expired - Lifetime
-
2004
- 2004-07-08 CA CA2473276A patent/CA2473276C/en not_active Expired - Fee Related
- 2004-07-14 BR BRPI0402741-8A patent/BRPI0402741B1/en not_active IP Right Cessation
- 2004-07-15 SG SG200404326A patent/SG108981A1/en unknown
- 2004-07-16 EP EP20040254292 patent/EP1498731B1/en active Active
- 2004-07-16 JP JP2004209303A patent/JP4651983B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| US7097783B2 (en) | 2006-08-29 |
| US20050011863A1 (en) | 2005-01-20 |
| EP1498731B1 (en) | 2015-05-20 |
| EP1498731A3 (en) | 2006-08-16 |
| CA2473276A1 (en) | 2005-01-17 |
| EP1498731A2 (en) | 2005-01-19 |
| BRPI0402741A (en) | 2005-05-17 |
| JP4651983B2 (en) | 2011-03-16 |
| JP2005036809A (en) | 2005-02-10 |
| BRPI0402741B1 (en) | 2012-05-29 |
| SG108981A1 (en) | 2005-02-28 |
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